Contact spring strip for attaching to a holding strip and contact part with a contact spring strip and a holding strip, especially a front panel of a printed circuit module

ABSTRACT

A contact spring connector that contains a holding strip, from which a contact spring leaf and a clamping leaf alternatingly extend in rows. A contact spring leaf has a contact leg, which is spread away from the holding strip and is connected with the holding strip via a cap area. A clamping leaf has a clamping leg connected with the holding strip by spring bands and from which a clamping element is spread away from between the spring bands. The decoupling of the contact spring leaf from the clamping leaf in particular results in ruggedness in respect to mechanical effects.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a contact spring connector for attachingcomponents of and associated with plug-in printed circuit boardassemblies.

1. Description of Related Art

A mounting rack is known from U.S. Pat. No. 4,631,641. It makes modulelocation slots available in an interior, which can be equipped withpluggable or plug-in printed board assemblies, which can be placedvertically and parallel next to each other. Each printed circuit boardhas a front panel on a front, which, for achieving electromagneticshielding, has strips on both linear sides, each of which projectstoward the pluggable printed board assembly. One of the strips is usedas a holding element for a contact socket connector, while the otherstrip is used as a counter-contact element for the contact socketconnector located on the front panel of an adjoining printed circuitboard. If the module location slots of one mounting rack are completelyequipped with pluggable printed board assemblies, then the front panelsof the pluggable printed board assemblies located next to each othercompletely cover the respective plug-in side of the mounting rack. Thegaps between the front panels are completely shielded in anelectromagnetically sealing manner by the contact socket connectors.

A module for being plugged into HF-sealed housings of electronicapparatus is taught by German Patent Reference DE 41 10 800 C1. Themodule also has a front panel with a U-shaped cross-sectional profile,wherein a socket connector, which has a plurality of spring elementsfollowing each other in a chain-like manner, is placed on one of the twolinear strips on one side of the front panel. Here, a spring element hastwo identically embodied contact springs, each with one spring leaf, aswell as a spring clamp with a clamping leaf. The spring elements extendfrom a common, flat rear leaf in such a way that the socket connectorhas an approximately U-shaped cross-sectional shape and can be pushedonto one of the two linear strips of the front panel in a clampingmanner such that the rear leaf rests on the inside of the linear strip,the clamping leaves rest on the outside of the linear strip and thespring leaves are spread away from exterior of the latter.

Finally, a contact socket connector for plugging on holding strips, inparticular on the front panels of shielded mounting racks and having aplurality of contact springs, which are connected in a chain-likemanner, is known from PCT International Application WO 96/39017. Eachcontact spring contains a cap area, which extends around a head area ofthe holding strip, a spring leaf which, starting at the cap area on thefront of the holding strip, spreads outward from a bent edge, and twolatching claws which, starting at the cap area, are spread out on thefront side of the holding strip at the bent edge and are relief-cut andlie on both sides next to the spring leaf. Each of the latching clawshas a holding lug with a latching edge spread away and upward toward thehead area. Finally, the contact socket connector has a holding leaf,which extends, starting in the cap area, to the back of the holdingstrip. At least one holding lug is cut out of the holding leaf and isspread away in the direction toward the rear of the holding strip.

Socket connectors used for contacting in the above mentionedapplications must satisfy numerous demands and are subjected todifferent stresses, in particular mechanical type stresses. Besides therequirement of providing a contacting force which is as evenly strongand continuous as possible over the entire length of the contact socketconnector, the mechanical resistance of the contact socket connectoragainst external influences is often of particular importance. For one,the latching of the contact socket connector on a holding strip, or alinear strip of a front panel, must be possible without resultingdamage. The contact socket connector must withstand any mechanicalstresses.

The latter can occur when a pluggable printed board assembly having afront panel and contact socket connector is pushed into the assignedmodule location slot in a mounting rack, or is pulled out. Thedeformations occurring because of the frictional movement along anadjoining front panel of a pluggable printed board assembly positionednext to it must not cause permanent damage to the associated contactsocket connector, either when it is being pushed in or pulled out.

Furthermore, a contact socket connector must also be designed so that nodamages occur even if, for example, an adjoining pluggable printed boardassembly equipped with projecting elements, for example electricalcomponents, heat sinks, pointed pins, wires and many others, is pushedinto or pulled out of a module location slot. If during movement of thepluggable printed board assembly the contact socket connector at thefront panel of an adjoining stationary pluggable printed board assemblyshould be brushed by the elements conducted past it, then no damage canbe caused to the contact socket connector, in particular when hooked byprojecting elements.

SUMMARY OF THE INVENTION

One object of this invention is to provide a contact socket connector ofthe above mentioned type in such a way that neither flat nor pointedobjects which are passed by the contact socket connector can causedamage. This object is achieved with a contact socket connector, theclaims and specification of which describe advantageous embodiment formsof the contact socket connector and a contact element used as a supportfor the contact socket connector.

BRIEF DESCRIPTION OF THE DRAWINGS

This invention and its advantages are explained in view of an exemplaryembodiment shown in the drawing figures wherein:

FIG. 1 is a perspective top view of a preferred embodiment of a contactsocket connector, in accordance with this invention;

FIG. 2 is a cross-sectional view of the preferred embodiment of thecontact socket connector in accordance with FIG. 1; and

FIG. 3 is a cross-sectional view of the preferred embodiment of acontact element on which a contact socket connector in accordance withFIGS. 1 and 2 is latched.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a perspective top view of a segment of a preferredembodiment of a contact socket connector 49, in accordance with theinvention, having a preferred flat holding strip 1, from which two pairsof respectively contact spring leaves 5 or 9, and a clamping leaf 3 or 7branch off, shown by the segment in FIG. 1. In actuality, a contactsocket connector has a considerably increased length in comparison withthe segment shown in FIG. 1, wherein respectively contact spring leafsand a clamping leaf alternatingly branch off in rows from the holdingstrip 1. The structure of the contact socket connector is explained ingreater detail by an example of the contact spring leaf 5 and theclamping leaf 3.

The contact spring leaf 5 essentially has a contact leg 27, which isspread away from the holding strip 1 and is connected with the holdingstrip 1 via a cap area 25, which is curved in an approximately U-shapedmanner. The contact leg 27 forms the actual contacting area of thecontact socket connector 49 because the contact leg 27 rests resilientlyon the surface of an adjoining element, making an electricallyconducting connection.

At an end 29 located opposite the cap area 25, and bent approximatelyU-shaped, the contact leg 27 is advantageously bent in a directiontoward the holding strip 1. The compact design of the contact springleaves of the contact socket connector 49 in accordance with thisinvention is insensitive to mechanical effects of any type. These act onthe contact spring leaves in the tangential direction in particular,which is indicated by a two-headed arrow 51 in FIG. 1.

The clamping leaf 3, which represents the second type of the elementswhich are alternatingly lined up on the holding strip 1, has a clampingleg 11, which is connected with the holding strip 1 by means of twospring bands 13 and 15, which are bent in an approximately U-shapedmanner. Finally, a clamping element 19 located between the spring bands13 and 15 spreads away starting at the clamping leg 11. Support of thecontact socket connector 49 is essentially provided by means of theclamping leaf 3 and its clamping element 19. The suspender-likeconnection of the clamping leg 11 on both sides by means of the twospring bands 13, 15 and the quasi symmetrical envelopment by the springbands 13, 15 of the clamping element 19 located in the relief-cut 17located between them, causes the support of the clamping leaf 3 on theholding strip 1 in a manner which is particularly rigid with respect toexternal mechanical effects.

The clamping element 19 is advantageously designed as a latching claw,which is spread away from the clamping leg 11 in the direction towardthe holding strip 1. Such an embodiment is shown in FIG. 1 and can beseen particularly clearly in the cross-sectional representation of thecontact socket connector in FIG. 2. The particularly secure support ofthe contact socket connector 49 on a holding strip can be achieved bymeans of a latching claw 19, which is quasi spread away upward andinward, on which the contact socket connector 49 is clipped. This willbe explained in greater detail as shown in FIG. 3.

Moreover, it is advantageous if the clamping leg 11 is inclined in thedirection toward the holding strip 1. Thus the adhesion of the contactsocket connector on a holding strip can be further improved. Such anembodiment has also already been illustrated in the example in FIG. 1and can be seen particularly clearly in the cross-sectionalrepresentation of the contact socket connector in FIG. 2. Finally, it isadvantageous if, on an end 21 located opposite the spring bands 13, 15,the clamping leg 11 is bent in the direction toward the holding strip 1.

In accordance with one embodiment of a contact socket connector of thisinvention shown in FIGS. 1, 2 and 3, the holding strip 1 has a latchinghook 23, which is bent off in the direction of an oppositely locatedcontact spring leaf, or clamping leaf, on the end which is locatedopposite the place where a contact spring leaf 5 or 9, and a clampingleaf 3 or 7 branch off. Such an embodiment can be clearly seen in thecross-sectional view in FIG. 2. Thus it is possible to improve thesupport of the contact socket connector 49 on a holding strip, which isexplained in greater detail in what follows by means of the example inFIG. 3.

With the design in accordance with this invention, of the clampingleaves and contact spring leaves of the contact socket connector, it ispossible to prevent, when one of the adjoining pluggable printed boardassemblies is pushed in or pulled out, catch points from projectingelements, for example electrical components, heat sinks, pointed pins,wires on the surface of adjoining pluggable printed board assemblies,during an inadvertent touching of the surface of a clamping leaf orcontact spring leaf, which cause local deformations of the contactsocket connector because of excessive use of force by the provokedoperators.

The design in accordance with this invention of a contact socketconnector 49 has a further advantage because it is particularly ruggeddue to the structural separation of the function of contacting from thefunction of clamping by means of separate contact spring leaves andclamping leaves separated from them. Thus, mechanical deformations ofcontact legs and cap areas of the contact spring leaves, whichunavoidably occur during activating or deactivating the contact socketconnector, have almost no effect on adjoining clamping leaves. Thelatter are almost completely mechanically uncoupled from the contactspring leaves, in particular because the approximately U-shaped curvedpairs of spring bands of the clamping leaves and the approximatelyU-shaped curved cap areas of contact spring leaves are separated, andare thus separately conducted around a holding strip located underneathand are separately seated on the holding strip. The holding strip aloneforms the element connecting all parts.

A portion of a contact element 45, which is used as a support for acontact socket connector 49, is shown in FIG. 3. For example, thiscontact element has the shape of a front panel of a pluggable printedboard assembly 47 attached to it. As a rule, such a front panel has aflat front, from whose front faces holding strips extend backward onboth sides. A holding strap 31 is present on the right front face of theexample shown in FIG. 3, on which a contact socket connector 49 of thetype described above has been clipped. Here, the U-shaped cap area 25 ofthe contact spring leaf 5 and the U-shaped spring bands 13, 15 enclosethe head area 33 of the holding strap 31. Furthermore, the holding strip1 rests on an inside 35, and in particular the clamping leg 11 of theclamping leaf 3 on an outside 37 of the holding strap 31. A clampingeffect is generated during this by the inclination of the clamping leg11 in the direction toward the holding strip 1, shown in FIG. 2, wherethe contact socket connector 49 is not clipped on. The contact leg 27 ofthe contact spring leaf 5 is spread away from the right outside 37 ofthe holding strap 31, which is clearly visible in FIG. 3.

In the example in FIG. 3, the clamping element 19 acts clampingly on theoutside 37 of the holding strap 31 in its head area 33. It isadvantageous if the holding strap 31 of the contact element 45 inaccordance with FIG. 3 has an additional first linear groove 39approximately in the head area 33, into which the at least one clampingelement 19 can snap.

In accordance with a further embodiment, also shown in FIG. 3, theholding strap 31 of the exemplary contact element has a second lineargroove 43 approximately in a base area 34 on the outside 37 for theinsertion of bent-off ends 21 or 29 of clamping legs 11 and contact legs27. The pivoting of the ends into this groove prevents the ends fromacting as catch points or impact edges and from representing a cause fordamage of the contact socket connector.

Finally, the holding strap 31 of the exemplary contact element has, inaccordance with a further embodiment as shown in FIG. 3, a third lineargroove 41 approximately in a base area 34 on the inside 35 for theengagement of bent-off latching hooks 23 at the lower end of the holdingstrip 1. It is thus possible to further improve the clamping effect ofthe contact socket connector 49 on the holding strap 31 of the contactelement 45.

What is claimed is:
 1. In a contact socket connector (49) for clippingon a holding strap (31), in particular a front panel (45) of a pluggableprinted board assembly (47), the improvement comprising: a holding strip(1), from which respectively a contact spring leaf (5, 9) and a clampingleaf (3, 7) alternatingly extend in a row-like manner, the contactspring leaf (5, 9) having a contact leg (27) spreading away from theholding strip (1) and connected via an approximately U-shaped curved caparea (25) with the holding strip (1), and the clamping leaf (3, 7)having a clamping leg (11) connected via two approximately U-shapedcurved spring bands (13, 15) with the holding strip (1) and from which aclamping element (19) is spread away between the spring bands (13, 15).2. In the contact socket connector in accordance with claim 1, whereinthe clamping leg (11) is inclined in a direction toward the holdingstrip (1).
 3. In the contact socket connector in accordance with claim1, wherein the clamping leg (11) is bent off in a direction toward theholding strip (1) at an end (21) located opposite the spring bands (13,15).
 4. In the contact socket connector in accordance with claim 1,wherein the contact leg (27) is bent off in the direction toward theholding strip (1) at an end (29) located opposite the U-shaped curvedcap area (25).
 5. In the contact socket connector in accordance withclaim 1, wherein the holding strip (1) has a latching hook (23) bent offtoward one of the contact spring leaf and the clamping leaf at an endportion located opposite a place where one of the contact spring leaf(5, 9) and the clamping leaf (3, 7) branch off.
 6. In the contact socketconnector in accordance with claim 1, wherein the clamping element (19)is formed as a latching claw spread away from the clamping leg (11) in adirection toward the holding strip (1).
 7. In the contact socketconnector in accordance with claim 6, wherein the clamping leg (11) isinclined in the direction toward the holding strip (1).
 8. In thecontact socket connector in accordance with claim 7, wherein theclamping leg (11) is bent off in the direction toward the holding strip(1) at an end (21) located opposite the spring bands (13, 15).
 9. In thecontact socket connector in accordance with claim 8, wherein the contactleg (27) is bent off in the direction toward the holding strip (1) at anend (29) located opposite the U-shaped curved cap area (25).
 10. In thecontact socket connector in accordance with claim 9, wherein the frontpanel (45) on the pluggable printed board assembly (47), having theholding strap (31) and a contact socket connector (49), which is slippedon the contact socket connector (49), wherein the holding strap (31) hasa second linear groove (43) approximately in a base area (34) forengagement of a bent-off end (21, 29) of at least one of the clampingleg (11) and the contact leg (27).
 11. In the contact socket connectorin accordance with claim 9, wherein the holding strip (1) has a latchinghook (23) bent off toward one of the contact spring leaf and theclamping leaf at an end portion located opposite a place where one ofthe contact spring leaf (5, 9) a nd the clamping leaf (3, 7) branch off.12. In the contact socket connector in accordance with claim 11, whereinthe front panel (45) on the pluggable printed board assembly (47), hasthe holding strap (31) and the contact socket connector (49), which canbe slipped on the contact socket connector (49), wherein the holdingstrap (31) has a third linear groove (41) approximately in a base area(34) for engagement of the bent-off latching hook (23) of the holdingstrip (1).
 13. In the contact socket connector in accordance with claim11, wherein a front panel (45) on a pluggable printed board assembly(47), having a holding strap (31) and a contact socket connector (49),is slipped on the contact socket connector (49).
 14. In the contactsocket connector in accordance with claim 13, wherein the holding strap(31) has a first linear groove (39) approximately in a head area (33)for engagement of at least one clamping element (19).
 15. In the contactsocket connector in accordance with claim 8, wherein the front panel(45) on the pluggable printed board assembly (47), having the holdingstrap (31) and the contact socket connector (49), which is slipped onthe contact socket connector (49), wherein the holding strap (31) has asecond linear groove (43) approximately in a base area (34) forengagement of a bent-off end (21, 29) of at least one of the clampingleg (11) and the contact leg (27).
 16. In the contact socket connectorin accordance with claim 15, wherein the front panel (45) on thepluggable printed board assembly (47), has the holding strap (31) andthe contact socket connector (49), which can be slipped on the contactsocket connector (49), wherein the holding strap (31) has a third lineargroove (41) approximately in a base area (34) for engagement of abent-off latching hook (23) of the holding strip (1).